It is known in the art to which this invention pertains to provide a suction accumulator between the evaporator and compressor of a refrigeration system in order to protect the compressor from possible damage. Vaporized refrigerant is received from the evaporator and passed on through the suction accumulator to the compressor. Any raw liquid is metered back to the compressor at a rate that will not result in damage to the compressor.
In recent years, primarily for reasons of energy savings and improved efficiency, it has often become the practice to flood the evaporator, or "low side" of the refrigeration system. This causes liquid refrigerant to spill back into the suction accumulator, wherein evaporation takes place, reducing the surface temperature of the accumulator below ambient dewpoint, which causes sweating of the accumulator surfaces. Sweating of the accumulator ultimately leads to rusting, and possible accumulation of water on the floor surfaces.
One expedient which has been employed in an effort to eliminate the sweating and ultimate rusting problems has been to wrap or encase the suction accumulator with one or more layers of insulation. However, this is costly from a material and labor standpoint. Also, difficulty has been encountered in providing an air-tight insulative seal, ultimately resulting in the described sweating and rusting problems.
It has further been proposed to position a suction accumulator within a receiver, and to admit into the space therebetween high temperature liquid refrigerant from the condenser. A structural arrangement of this character is shown in U.S. Pat. No. 3,212,289. As is described therein, the relatively warm refrigerant prevents moisture in the atmosphere from condensing on the accumulator which contains relatively cold refrigerant. The patented arrangement also provides an efficient heat exchange between the relatively cold low pressure refrigerant in the accumulator and the relatively warm high pressure refrigerant in the receiver.